long oldPosition = sourceChannel.position();
      long position = oldPosition;
      long copied;
      do {
        copied = sourceChannel.transferTo(position, ZERO_COPY_CHUNK_SIZE, to);
        position += copied;
        sourceChannel.position(position);
      } while (copied > 0 || position < sourceChannel.size());
      return position - oldPosition;
    }

      }
      return crossOverUp(index, x);
    }

    /**
     * Fills the hole at {@code index} by moving in the least of its grandchildren to this position,
     * then recursively filling the new hole created.
     *
     * @return the position of the new hole (where the lowest grandchild moved from, that had no
     *     grandchild to replace it)
     */
    int fillHoleAt(int index) {

    }
    return this;
  }

  @Override
  @CanIgnoreReturnValue
  public Hasher putBytes(ByteBuffer b) {
    if (b.hasArray()) {
      putBytes(b.array(), b.arrayOffset() + b.position(), b.remaining());
      Java8Compatibility.position(b, b.limit());
    } else {
      for (int remaining = b.remaining(); remaining > 0; remaining--) {
        putByte(b.get());
      }
    }
    return this;
  }

  @Override

      }
    };
  }

  /**
   * Advances {@code iterator} {@code position + 1} times, returning the element at the {@code
   * position}th position.
   *
   * @param position position of the element to return
   * @return the element at the specified position in {@code iterator}
   * @throws IndexOutOfBoundsException if {@code position} is negative or greater than or equal to

   * Ensures that {@code start} and {@code end} specify valid <i>positions</i> in an array, list or
   * string of size {@code size}, and are in order. A position index may range from zero to {@code
   * size}, inclusive.
   *
   * @param start a user-supplied index identifying a starting position in an array, list or string
   * @param end a user-supplied index identifying an ending position in an array, list or string

    };
  }

  /**
   * Returns the element at the specified position in an iterable.
   *
   * <p><b>{@code Stream} equivalent:</b> {@code stream.skip(position).findFirst().get()} (throws
   * {@code NoSuchElementException} if out of bounds)
   *
   * @param position position of the element to return
   * @return the element at the specified position in {@code iterable}

      if (byte1 < (byte) 0xE0) {
        // Two-byte form.
        if (index == end) {
          return false;
        }
        // Simultaneously check for illegal trailing-byte in leading position
        // and overlong 2-byte form.
        if (byte1 < (byte) 0xC2 || bytes[index++] > (byte) 0xBF) {
          return false;
        }
      } else if (byte1 < (byte) 0xF0) {
        // Three-byte form.

    setSucceeds(lastEntry, entryIndex);
    setSucceeds(entryIndex, ENDPOINT);
  }

  @Override
  void accessEntry(int index) {
    if (accessOrder) {
      // delete from previous position...
      setSucceeds(getPredecessor(index), getSuccessor(index));
      // ...and insert at the end.
      setSucceeds(lastEntry, index);
      setSucceeds(index, ENDPOINT);
      incrementModCount();
    }

   * returned by {@code get(rowKeyList().get(rowIndex), columnKeyList().get(columnIndex))}, but this
   * method runs more quickly.
   *
   * @param rowIndex position of the row key in {@link #rowKeyList()}
   * @param columnIndex position of the row key in {@link #columnKeyList()}
   * @return the value with the specified row and column

   * @param array the array of elements to append
   * @return an array whose size is one larger than {@code array}, with {@code element} occupying
   *     the first position, and the elements of {@code array} occupying the remaining elements.
   */
  public static <T extends @Nullable Object> T[] concat(@ParametricNullness T element, T[] array) {
    T[] result = newArray(array, array.length + 1);